The present invention relates generally to the field of skis, and more particularly to a release binding and brake for telemark and cross-country skis.
Ski release bindings for skis are well known in the art such as shown in U.S. Pat. Nos. 3,877,712; 4,348,036; 4,621,828; 4,348,036; and 5,518,264. The most widely used telemark release binding uses a cable around the heel of the boot. Ski bindings that are easier to use and provide greater safety would enhance the enjoyment of the sport.
Ski brakes are also well known in the art and have substantially supplanted the use of tethers between skis and skiers. Typically the brakes are spring activated to project pawls nominally downward below the bottoms of the skis to engage the snow. They are disengaged when the skiers step on their tops with their boots swinging the pawls up along the sides of the skis. This spring style of brake has not been adapted to telemark and cross-county skis because the heels of the boots are not fixed.
The present invention is directed to an improved release binding and brake for telemark and cross-country skis. Instead of fastening the toe plate directly to the ski, a release plate is positioned between a toe plate and the ski. Inside the release plate is a planar load spring having two sides forming an elongated central aperture which is accessible through a top hole. In U.S. Pat. Nos. 6,092,830 and 6,322,095 by applicant, a load spool having a circumferential groove is attached to the bottom of the toe plate. To install the toe plate on the ski, the skier positions the load spool in the hole in the release plate and pushes down with his weight to engage the groove of the load spool in the spring and hold the toe plate to the ski.
In the present preferred embodiment of the invention, the cross section of the holding portion of the load spool is substantially elliptical, not cylindrical, and is rotatable by means of a lever extending outside the toe plate. When the skier wants to step into the spring to engage the ski on/the spool, the force required is minimized by moving the lever to rotate the spool so that the minor axis of the ellipse is perpendicular to the two sides of the spring. When the skier want to ski, the force required to pull the spool out of the spring is maximized by using the lever to rotate the spool so that the major axis of the ellipse is perpendicular to the two sides of the spring.
In accordance with an important aspect of the invention, the step in force is substantially 70 percent of the weight of the skier while the pullout force is substantially 250 percent of the weight of the skier.
In accordance with another preferred embodiment, a spring type brake is positioned under the toe plate. The position of the brake is determined entirely by the presence or absence of the toe plate. If the toe plate is present, the top of the spring brake is down forcing the pawls of the brake up. If the toe plate is absent, the spring activates forcing the pawls of the brake down to engage the snow and stop the ski.